Based solely on your statement the only possible conclusion one can draw is that in a best case scenario your method is equally effective to the "castle doctrine" I utilize since I too have never lost any birds to predators/neighbor dogs, ect and I've never used an electric fence. Not that I wouldn't I just never have to. I can go out into the yard and see the effectiveness of my own marksmanship. The birds go where they want and the predators don't really come around anymore. No drama, no traumatized chickens, just happy healthy chickens. I have yet to encounter a problem that my .308 can fix once and for all. Problems seem to for whatever reason, try and avoid me. Wierd, I know. But all I can do is relate my own experiance.
EDIT: Nothing better than gloves lined with racoon fur on a chilly day. They also make nice hats, I'm told.
I have been keeping chickens for a few days now so feel expert enough to give a heads up to those that might follow your advice. It is not a big deal at all to go years between losses to predators / dogs, even without any sort of defenses. On front and back of such lulls in losses you can get hammered. The firearm stuff I am just as capable of as you but have a couple slight problems. First is I have a job that is not in the home or on the property in close proximity to the chickens. Second is I sleep. What complicates all this is the predator does not alert me before taking first chicken even when I am home nor does the predator make arrangements so I can be home to meet it like the person that gives me quotes on contractual work. I have to be present to shoot.